1. Field
Embodiments of the present invention relate to display devices with touch input devices and, more specifically, systems and methods for reducing display lag between the touch input device and the display device.
2. Related Art
Display panels incorporating or coupled to overlaid touch sensor panels provide an interaction system for touch-enabled computing devices such as mobile phones, tablet computers, laptop computers, and desktop computers. In such computing devices, graphics are displayed on the display panel and a user can interact with these devices by touching the screen (e.g., using an active stylus, a passive stylus, or a body part such as a finger), thereby providing an intuitive user interface.
Touch events detected by the touch sensor panels are typically processed by high level application software running on an application processor (AP) of the device. The many processing steps between the touch sensor panel and the AP and the non-deterministic processing time on the AP (including delays due to other computational tasks being performed by the AP) introduce high levels of latency (e.g., 70 to 150 milliseconds) that reduce responsiveness of the computing device to the user's touch inputs.
Some empirical studies have indicated that most humans can detect even a 30 millisecond asynchrony between senses, such as touch and vision (see, e.g., Keetels, M. and Vroomen, J. (2012). Perception of Synchrony Between the Senses. In M. M. Murray and M. T. Wallace (Eds.), Frontiers in the neural basis of multisensory processes (pp. 147-177). London: Taylor & Francis Group). Delays of 50 to 150 milliseconds would be detectable to most of users of these computing devices, which could lead to increased user frustration due to the failure of the computing device to immediately provide feedback to the user's input.